[Federal Register Volume 65, Number 35 (Tuesday, February 22, 2000)]
[Rules and Regulations]
[Pages 8642-8645]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-3796]


-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 95-NM-150-AD; Amendment 39-11580; AD 2000-03-20]
RIN 2120-AA64


Airworthiness Directives; Airbus Model A300-600 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

[[Page 8643]]


ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to all Airbus Model A300-600 series airplanes, that requires 
repetitive ultrasonic inspections to detect cracks on the forward 
fittings in the radius of frame 40 adjacent to the tension bolts in the 
center section of the wings, and various follow-on actions. This 
amendment is prompted by reports of cracking due to fatigue-related 
stress in the radius of frame 40 adjacent to the tension bolts at the 
center/outer wing junction. The actions specified by this AD are 
intended to detect and correct fatigue cracking on the forward fittings 
in the radius of frame 40 adjacent to the tension bolts in the center 
section of the wings, which could result in reduced structural 
integrity of the wings.

DATES: Effective March 28, 2000.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of March 28, 2000.

ADDRESSES: The service information referenced in this AD may be 
obtained from Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707 
Blagnac Cedex, France. This information may be examined at the Federal 
Aviation Administration (FAA), Transport Airplane Directorate, Rules 
Docket, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of 
the Federal Register, 800 North Capitol Street, NW., suite 700, 
Washington, DC.

FOR FURTHER INFORMATION CONTACT: Norman B. Martenson, Manager, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2110; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to all Airbus Model A300-600 series 
airplanes was published as a supplemental notice of proposed rulemaking 
(NPRM) in the Federal Register on November 24, 1998 (63 FR 64918). That 
action proposed to require repetitive ultrasonic inspections to detect 
cracks on the forward fittings in the radius of frame 40 adjacent to 
the tension bolts in the center section of the wings, and various 
follow-on actions.

Comments

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.
    One commenter, an operator, has no comments on the proposed 
supplemental NPRM, except to report that the ultrasonic inspections 
have been accomplished on part of its fleet, with no findings of 
cracking as yet.

Clarification of Flight Hour Thresholds

    One commenter, the manufacturer, states that it cannot determine 
how the flight hour thresholds specified in the supplemental NPRM were 
calculated by the FAA. The FAA infers that the commenter is requesting 
clarification regarding the requirement to accomplish the initial 
inspection at ``7,250 total landings or 17,700 total flight hours, 
whichever occurs first,'' as specified in paragraph (a)(1)(i) of the 
supplemental NPRM.
    The FAA herewith provides the requested information. The threshold 
of 7,600 total landings specified in Airbus Service Bulletin A300-57-
6062, Revision 02, dated January 29, 1997, is calculated using the 
``adjustment-for-range'' formula and a fatigue rating of 0.13, and is 
valid for airplanes having an average flight time (AFT) of 2.1 hours. 
(Airbus Service Bulletin A300-57-6062, Revision 02, was referenced in 
the supplemental NPRM as the appropriate source of service information 
for this AD.) At the time the supplemental NPRM was developed, the AFT 
for all Airbus Model A300-600 airplanes operated in the United States 
was 2.45 hours. The FAA used the 2.45 AFT and the ``adjustment-for-
range'' formula to obtain an adjustment factor appropriate for 
airplanes on the U.S. Register, as follows:

1-[(2.45-2.1) * 0.13] = 0.9545
0.9545 7,600 = 7,254.

Additionally, the FAA multiplied the 2.45 AFT by the adjusted landing 
threshold to obtain an approximation of the corresponding flight hours, 
as follows:

7,254 * 2.45 = 17,773.

    Using these calculations, the FAA determined appropriate landing 
and flight-hour thresholds, previously described, for the requirements 
of this AD.

Request To Revise Compliance Threshold

    The same commenter requests that the supplemental NPRM be revised 
to replace the compliance thresholds with thresholds calculated using a 
new method. The commenter states that the flight-hour thresholds 
specified in the supplemental NPRM seem to be overly conservative for 
operators utilizing airplanes in long-range operations; such thresholds 
will penalize those operators by requiring inspections earlier than 
necessary. The commenter states that, in order to avoid using the 
current ``adjustment-for-range'' formula for calculating compliance 
times, an alternative method has been developed. This new method will 
provide constant flight-hour thresholds and intervals in addition to 
the flight cycle-based thresholds and intervals. The commenter proposes 
to provide these additional thresholds to the FAA, calculated in 
accordance with the new method.
    The FAA does not concur. The FAA has reviewed the alternative 
method proposed by the manufacturer for calculating flight-hour 
thresholds, and has discussed the requirements of this AD further with 
the manufacturer and with the Direction Generale de l'Aviation Civile 
(DGAC), which is the airworthiness authority for France. The FAA 
concurs technically with use of such flight-hour and flight-cycle 
thresholds and intervals. However, the revised thresholds have not yet 
been made available to the FAA for its review, and the manufacturer 
advises that there has been a delay in internal review and approval of 
the thresholds. The FAA does not consider it appropriate to further 
delay issuance of this AD while awaiting the receipt of these data. 
Therefore, the FAA has determined that it is necessary to issue the AD 
with the currently specified thresholds. Once revised thresholds are 
made available, the FAA will review them and determine if further 
rulemaking is necessary. Additionally, under the provisions of 
paragraph (d)(1) of the AD, the FAA may approve requests for 
adjustments to the compliance time if data are submitted to 
substantiate that such adjustments of the compliance time would provide 
an acceptable level of safety.

Conclusion

    After careful review of the available data, including the comments 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule as proposed.

Cost Impact

    The FAA estimates that 35 airplanes of U.S. registry will be 
affected by this AD. It will take approximately 2 work hours per 
airplane (1 work hour per side) to accomplish the required ultrasonic 
inspection, at an average labor rate of $60 per work hour. Based on 
these figures, the cost impact of the AD on U.S. operators is estimated 
to be

[[Page 8644]]

$4,200, or $120 per airplane, per inspection cycle.
    The cost impact figure discussed above is based on assumptions that 
no operator has yet accomplished any of the requirements of this AD 
action, and that no operator would accomplish those actions in the 
future if this AD were not adopted.

Regulatory Impact

    The regulations adopted herein will not have a substantial direct 
effect on the States, on the relationship between the national 
Government and the States, or on the distribution of power and 
responsibilities among the various levels of government. Therefore, it 
is determined that this final rule does not have federalism 
implications under Executive Order 13132.
    For the reasons discussed above, I certify that this action (1) is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979); and (3) will not have a 
significant economic impact, positive or negative, on a substantial 
number of small entities under the criteria of the Regulatory 
Flexibility Act. A final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it may be obtained 
from the Rules Docket at the location provided under the caption 
ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends part 39 of 
the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39--AIRWORTHINESS DIRECTIVES

    1. The authority citation for part 39 continues to read as follows:

    Authority:  49 U.S.C. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

2000-03-20  Airbus Industrie: Amendment 39-11580. Docket 95-NM-150-
AD.

    Applicability: All Model A300-600 airplanes, certificated in any 
category.

    Note 1:  This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
modified, altered, or repaired in the area subject to the 
requirements of this AD. For airplanes that have been modified, 
altered, or repaired so that the performance of the requirements of 
this AD is affected, the owner/operator must request approval for an 
alternative method of compliance in accordance with paragraph (d)(1) 
of this AD. The request should include an assessment of the effect 
of the modification, alteration, or repair on the unsafe condition 
addressed by this AD; and, if the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.

    Compliance: Required as indicated, unless accomplished 
previously.
    To detect and correct fatigue cracking on the forward fittings 
in the radius of frame 40 adjacent to the tension bolts in the 
center section of the wings, which could result in reduced 
structural integrity of the wings, accomplish the following:

Inspections and Corrective Actions

    (a) Perform an ultrasonic inspection to detect cracking on the 
forward fittings in the radius of frame 40 adjacent to the tension 
bolts in the center section of the wings, in accordance with Airbus 
Service Bulletin A300-57-6062, Revision 02, dated January 29, 1997, 
at the applicable time specified in either paragraph (a)(1) or 
(a)(2) of this AD.
    (1) For airplanes that have accumulated fewer than 9,100 total 
landings or 22,300 total flight hours as of the effective date of 
this AD: Inspect at the later of the times specified in either 
paragraph (a)(1)(i) or (a)(1)(ii) of this AD.
    (i) Prior to the accumulation of 7,250 total landings or 17,700 
total flight hours, whichever occurs first.
    (ii) Within 1,500 landings after the effective date of this AD.
    (2) For airplanes that have accumulated 9,100 total landings or 
more and 22,300 total flight hours or more as of the effective date 
of this AD: Inspect within 750 landings after the effective date of 
this AD.

    Note 2:  Inspections that were accomplished prior to the 
effective date of this AD in accordance with Airbus Service Bulletin 
A300-57-6062, Revision 1, dated July 23, 1995, are considered 
acceptable for compliance with paragraph (a) of this AD.

    (b) If no crack is detected during the inspection required by 
paragraph (a) of this AD, repeat the ultrasonic inspection required 
by that paragraph thereafter at intervals not to exceed 6,500 
landings or 16,000 flight hours, whichever occurs first; in 
accordance with Airbus Service Bulletin A300-57-6062, Revision 02, 
dated January 29, 1997.
    (c) If any crack is detected during any inspection required by 
paragraph (a) or (b) of this AD, prior to further flight, install an 
access door, and perform an eddy current inspection to confirm the 
presence of a crack; in accordance with Airbus Service Bulletin 
A300-57-6062, Revision 02, dated January 29, 1997. Accomplishment of 
this eddy current inspection terminates the repetitive inspection 
requirement of paragraph (b) of this AD.
    (1) If no crack is detected during the eddy current inspection, 
repeat the eddy current inspection, in accordance with the service 
bulletin, thereafter at intervals not to exceed 6,500 landings or 
16,000 flight hours, whichever occurs first.
    (2) If any crack is detected during any eddy current inspection 
performed in accordance with paragraph (c) or (c)(1) of this AD, 
prior to further flight, blend out the crack and repeat the eddy 
current inspection in accordance with the service bulletin.
    (i) If the eddy current inspection performed after the blend-out 
shows that the crack has been removed, and if the blend-out is equal 
to or less than 50 millimeters (mm) long and equal to or less than 2 
mm deep, thereafter repeat the eddy current inspection at intervals 
not to exceed 2,800 landings or 7,000 flight hours, whichever occurs 
first.
    (ii) If the eddy current inspection performed after the blend-
out shows that the crack has not been removed, or if the blend-out 
is more than 50 mm long or more than 2 mm deep, prior to further 
flight, repair in accordance with a method approved by the Manager, 
International Branch, ANM-116, FAA, Transport Airplane Directorate; 
or the Direction Generale de l'Aviation Civile (or its delegated 
agent).

Alternative Methods of Compliance

    (d)(1) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Manager, International Branch, ANM-116. 
Operators shall submit their requests through an appropriate FAA 
Principal Maintenance Inspector, who may add comments and then send 
it to the Manager, International Branch, ANM-116.
    (2) Operators may request an extension to the compliance times 
of this AD in accordance with the ``adjustment-for-range'' formula 
found in Paragraph 1.B.(5) of Airbus Service Bulletin A300-57-6062, 
Revision 02, dated January 29, 1997; and provided in A300-600 
Maintenance Review Board, Section 5, Paragraph 5.4. The average 
flight time per flight cycle (landing) in hours used in this formula 
should be for an individual airplane. Average flight time for a 
group of airplanes may be used if all airplanes of the group have 
flight times differing by no more than 10 percent. If compliance 
times are based on the average flight time for a group of airplanes, 
the flight times for individual airplanes of the group must be 
included for FAA review.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the International Branch, ANM-116.

Special Flight Permits

    (e) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate the airplane to a location where 
the requirements of this AD can be accomplished.

Incorporation by Reference

    (f) Except as required by (c)(2)(ii) of this AD, the actions 
shall be done in accordance with Airbus Service Bulletin A300-57-
6062,

[[Page 8645]]

Revision 02, dated January 29, 1997, which contains the specified 
effective pages:

------------------------------------------------------------------------
                              Revision level shown
          Page No.                   on page         Date shown on page
------------------------------------------------------------------------
1-34, 37....................  02..................  Jan. 29, 1999
35, 36......................  1...................  Jul. 23, 1995
------------------------------------------------------------------------

This incorporation by reference was approved by the Director of the 
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 
51. Copies may be obtained from Airbus Industrie, 1 Rond Point 
Maurice Bellonte, 31707 Blagnac Cedex, France. Copies may be 
inspected at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue, SW., Renton, Washington; or at the Office of the Federal 
Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

    Note 4: The subject of this AD is addressed in French 
airworthiness directive 95-063-177(B)R3, dated July 2, 1997.

    (g) This amendment becomes effective on March 28, 2000.

    Issued in Renton, Washington, on February 11, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-3796 Filed 2-18-00; 8:45 am]
BILLING CODE 4910-13-P